1. Technical Field
The present invention relates to prolongation of operating time of a secondary battery (hereinafter simply referred to as “battery”). More particularly, the present invention relates to prolongation of the battery operating time with an eye on voltage drop that occurs immediately after charging.
2. Background Art
Currently, various devices such as mobile phones, laptop computers, portable video game players and digital cameras are equipped with batteries. These devices are provided with a variety of applications such as audio player and video player. In order to use such applications for a long time, the batteries that can be used for a longer period of time are demanded.
To meet such demands, many techniques to detect voltage drop caused by power consumption and reduce the load on the batteries are disclosed. For example, the following patent document 1 discloses a technique to reduce power consumption and delay the end of discharging by decreasing the brightness of an LTD or extending a low brightness period while LTD is blinking, if the voltage falls below a certain threshold level in the course of monitoring of the voltage.    Patent document 1: Japanese Laid-open Patent Application Publication No. 2004-72212    Nonpatent document 1: Denchi Binran (“Battery Handbook”) compiled by Yoshiharu Matsuda and Zen-ichiro Takehara, Maruzen Co., Ltd    Issued on Aug. 20, 1990
However, there is a demand for a new technique that enables batteries to operate longer. Therefore, the present invention aims to provide a battery-driven device, a load control method, an integrated circuit and a load control program that enable a battery to operate for a prolonged period of time.